Self-ejecting key



Jain. 57, 1942. w. SPIRO I 2,271,048

SELF-EJECTING KEY Filed Mai-ch 1a, 1940 INVENTOR 244 1161" *5) 52 0 WI!M ATTORNE Patented Jan. 27, 1942 UNITED STATES v PATENT OFFICEApplication March 18, 5:23;. 324,548

Claims.

This invention relates to keys, and more particularly refers toimprovements in keys of the self-ejecting type, comprising means wherebya the key will automatically be ejected from a lock or other mechanismcontrolled thereby, after either one of two extreme positions thereofhas been reached.

It is well known that, after opening or closing a door, one is apt,through inadvertence, frequently to leave the key in the. lock. It isalso a common occurrence, for motorists, after turnmodification of thelockor other mechanism.

Another object is to provide, in a key, key

P18. 6 is a sectional view of the same in an enlarged scale, throughline 6-6 of Fig. 5.

According to my invention, the key is provided with a normally extendedspring-acting abutment member resting against the face of the barrelwhen the key is inserted in the key slot. and yielding under pressure asthe key is advanced within the slot; said abutment member automaticallyresuming its extended position, and forcibly ejecting the key from theslot, when the key is released, if the barrel has been moved to aposition where the key is not retained by the lock structure.

ejecting means of a simple, novel and improvedconstruction, requiringonly minor changes in the construction of the key itself, without undulyweakening the key structure, and without increasing the bulk of the keyto an objectionable extent.

A further object of the invention is to provide a self-ejecting keyreadily insertable in a lock of standard construction, said key beingautomatically ejected from the lock when it reaches either the locked orunlocked position, as may- .Fig. 3 is a perspective view of a lockcasing oi ordinary construction, showing the key of Fig. 1 inserted inthe lock to turn the barrel from one of its extreme positions to theother;

Fig. 4 is a side view in elevation of a key embodying myinvention in analternative form;

Fig. 5 is a similar view, partly sectioned to show the construction ofthe key ejecting means; and

The provision in 'a key, of a spring-acting abutment memberautomatically ejecting the key from the look when a given position hasbeen reached, is not in a broad sense new. Such constructions as havecome to my notice, however, have'proved impractical for some reason orother. In some cases the character of the ejecting means is such as torender the key bulky to an objectionable extent. In other cases theejecting means is designed so as to require for its application theremoval of a sizable portion of the key shank, thus excessivelyweakening the key structure; while where the key is of small size,constructional limitations effectively prevent its being equipped withthe ejecting means altogether.

In the arrangement forming the subject of my invention, thespring-acting abutment member extends'along the back edge of the keyshank, and projects outwardly therefrom at least in the plane oftheshank, and preferably also trans- 'versely of said plane. In thepreferred construction a spring is directly used as abutment member, andthis results in an exceedingly simple construction, requiring only thecutting of a narrow longitudinal slot in proximity of theback edge ofthe key shank, and the insertionotthe coils of the spring .therethrough,said coils encircling the narrow' portion of the shank interveningbetween the slot and theback edge.

Referring to Figs. 1 to 3 of the drawing, l0 designates the face plateof a lock ll of ordinary construction, for instance the ignition lock ofan automobile. The lock is provided with a barrel l2, provided with akey slot l3 opening on the face ll of the barrel,

The key, shown in detail in Figs. 1 and 2, comprises a handle portion l5and a shank l6 frontwardly extending therefrom, the key being of usualconstruction, slightly modified for the apthrough, and turning thespring.-I cause all the coils of said spring to eventually p ss throughsaid slot and encircle the bar portion 2i intervening between the slotand the back edge.

In order to provide a. good abutment for the spring, I prefer to cut astraight bottomed notch 22 in the handle portion at the base of theshank, said notch reaching as far as the inner end of the slot 20. Bythus extending the seat of the spring within the handle portion, Iinsure sufilcient room for the spring to contract when the key is in thelock, as shown in Fig. 8, without causing an excessive or permanentdeformation of said spring, thus insuring it effective elastic action atall times.

It will be observed that the spring need only be made of very lightgauge wire, so that the slot 20 may accordingly be very narrow,necessitating the removal of but a 'small fraction of the materialcomposing the shank. Furthermore the strength of the shank i still lessimpaired if the slot is cut in close proximity of the back edge, asshown, so as to leave the transversal section of the main portion of theshank as close to the original section as may be consented by the widthof the bar portion 2 I. r

Fig. 2 clearly shows that the spring projects outwardly of the back edgeof the shank both in the plane of the shank and laterally thereof, sothat even though the spring has a relatively small diameter, it willconstitut an effective abutment member engaging the face of the barrelwhen the key is inserted in the look.

It is obvious that the proposed arrangement is of the utmost simplicityand applicable to practically any key by the expenditure of littlelabor, without entailing any change in the lock, and practically withoutimpairing the strength Of the key. However, if even a small measure ofweakening on the key should be objectionable, the original strength ofthe key, and more, may be restored by making the key of stainless steelor similar material, in place of the relatively soft alloy usuallyemployed.

The arrangement illustrated in Figs. 4 to 6 is somewhat more elaboratethan the one just described, although it shares with it the feature ofproviding the key shank with a yielding abutment member extending alongand projecting from its back edge. The key is also in this casecomposed, as usual, of a handle portion 23 and a shank 24 extendingtherefrom. Most keys of this character have one or more longitudinalgrooves 25, 26, and by utilizing one of these grooves as a guide orpassageway for the yielding abutment member I altogether avoid weakeningof the key shank such as would be due to the cutting of a through slot.

The part of the handle portion adjacent the back edge of the shank isremoved, leaving the remaining part formed with a straight upper edge 21parallel .to but slightly offset from the back edge 28, the length ofsaid upper edge substantially corresponding to the length of a hollowcylinder or housing 29 fixed thereto by welding or otherwise so as toform an extension of the handle portion 23, symmetrical to the planethereof. Said housing is closed at the rear, as shown at an, and open atthe front to permit the ber 3|, arranged in telescopic relationtherewith,

and retractible within said housing.

Said plunger member has a closed front end 12, and is open at the rear,forming with the housing a'continuous longitudinal chamber 33, withinwhich is contained a normally extended compressible spiral spring llabutting against the rear end of the housing and the front end of theplunger member, said spring normally il ing the plunger member to itsextended position, where its front end remains in close proximity of thefront end of the shank. The front extension of the plunger member islimited in any suitable manner, for instance, by slightly tuming in theedge of the front end of the housing, and tuming out the edge of therear end of the plunger member to form abutting flanges 35, 30,respectively.

The front of the plunger member is formed with two depending lugs I1,38, abutting one against each side of the shank to prevent turningmovement of the plungenmember, one at least of said lugs, I1, having itstip end turned in to engage one of the grooves 25 in the shank,

as shown in Fig. 5. This insures a smooth operation of the plungermember during it move ment of retraction and extension. The partsmentioned are so proportioned that the spring 84 preferably restsdirectly against the back edge 28 of the shank, the whole forming a verycompact and effective arrangement. By virtue of this construction thekey maintains intact its original strength, and since the diameter ofthe spring and the housing and plunger member can be made very small,the bulk of the key is not materially or objectionably increased.

Minor constructional details may vary from those shown without departingfrom the inventive idea; the drawing should therefore b unpassagetherethrough of a hollow plunger mem- 76 derstood as being intended forillustrative purposes only, and not in a limiting sense. I accordinglyreserve the right to carry my invention into practice in all those waysand manners as may enter, fairly, into the scope of the appended claims.

I claim:

1. A self-ejecting key comprising a handle portion and a shankfrontwardly extending therefrom, said shank having a tumbler engagingfront edge and a back edge and being provided with a longitudinalpassageway, and a lock engaging normally extended longitudinallyresilient abutment means interlocking with said passageway, saidabutment means extending along and projecting rearwardly of said backedge.

2. A self-ejecting key comprising a handle portion and a shankfrontwardly extending therefrom, said shank having a tumbler engagingfront edge and a back edge and being provided with a longitudinalpassageway, and a lock engaging normally extended longitudinallyresilient abutment means interlocking with said passageway, saidabutment means extending along and projecting rearwardly of said backedge, both in the plane of said shank and laterally thereof.

3. A self-ejecting key comprising a handle portion and a shankfrontwardly extending therefrom, said shank having a tumbler engagingfront edge and a back edge and being provided with a longitudinal slot,and a normally extended compressible spiral spring having its coilspassing through said slot, encircling the portion of said shankintervening between said slot and the back edge of said shank. Y

4. A self-ejecting key comprising a handle portion and a shankfrontwardly' extending there-' tion and a shank frontwardly extendingtherefrom, said shank having a tumbler engaging front edge and a backedge, a longitudinally directed housing member integral with said handleportion, a lock engaging plunger member mounted in telescopic relationto said housing member, ex-

tending along and outwardly projecting from said back edge, and aresilient compression member interposed between said housing member andsaid plunger member.

6. A self-ejecting key comprising a handle portion and a shankfrontwardly extending therefrom, said shank having a tumbler engagingfront edge and a back edge, a longitudinally directed housing memberintegral with said handle portion, a lock engaging plunger membermounted in telescopic relation to said housing member, ex-

tensible from, and slidable within said housing member, said plungermember extending along and outwardly projecting from said back edge, anda resilient compression member interposed between said housing memberand said plunger member.

7. A self-ejecting key comprising a handle portion and a shankfrontwardly extending therefrom, said shank having a tumbler engagingfront edge and a back edge, a longitudinally directed housing memberintegral with said handle portion, a lock engaging plunger membermounted in telescopic relation to said housing member, extensible from,and slidable within said housing member, said plunger member extendingalong and outwardly projecting from said back edge, and a resilientcompression member interposed between said housing member and saidplunger member, the rear end of said plunger member being adapted toengage the front end of said housing member to limit the outwardmovement of said plunger member.

8. A self-ejecting key comprising a handle portion and a shankfrontwardly extending therefrom, said shank having a tumbler engagingfront edge and a back edge, a longitudinally directed housing memberintegral with said handle portion, a hollow lock engaging plunger membermounted in telescopic relation to said housing member, extensible from,and slidable within said housing member, said plunger member extendingalong and outwardly projecting from said back edge, and a compressiblespiral spring within said housing and plunger member, normally retainingsaid plunger member in its extended position.

9. A self-ejecting key comprising a handle portion and a shankfrontwardly extending therefrom, said shank having a tumbler engagingfront edge, and being provided with a longitudinal groove, alongitudinally directed housing member integral with said handleportion, a lock engaging plunger member mounted in telescopic relationto said housing member, extending along and outwardly projecting fromsaid back edge, and a resilient compression member interposed betweensaid housing member and said plunger member, said plunger member havingtwo depending lug's at the front abutting one against each side of saidshank, one of said lugs extending and riding within said groove.

10. A self-ejecting key comprising a handle portion and a shankfrontwardly extending therefrom, said shank having a tumbler engagingfront edge and a back edge, and being provided with a longitudinalgroove, a longitudinally directed housing member integral with saidhandle portion, a lock engaging plunger member mounted in telescopicrelation to said housing member, extensible from, and slidable withinsaid housi member, said plunger member extending along and outwardlyprojecting from said back edge,

and a compressible spiral spring within said housing and plunger member,normally retaining said plunger member in its extended position, saidplunger member having two depending lugs at the front abutting oneagainst each side of said shank, one of said lugs extending and ridingwithin said groove.

WALTER SPIRO.

